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<h1 id="firstHeading" class="firstHeading">&#21464;&#21442;&#25968;&#20989;&#25968;</h1>
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<div id="contentSub"><span class="subpages">&lt; <a href="cpp.html">cpp</a>&lrm; | <a href="cpp-utility.html">utility</a></span></div>
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<p>&#21464;&#21442;&#25968;&#20989;&#25968;&#26159;&#25509;&#25910;<a href="cpp-language-variadic_arguments.html">&#21487;&#21464;&#25968;&#37327;&#21442;&#25968;</a>&#30340;&#20989;&#25968;&#65288;&#20363;&#22914; <span class="t-lc"><a href="cpp-io-c-fprintf.html">std::printf</a></span> &#65289;&#12290;</p>
<p>&#20026;&#22768;&#26126;&#21464;&#21442;&#25968;&#20989;&#25968;&#65292;&#30465;&#30053;&#21495;&#35201;&#20986;&#29616;&#22312;&#21442;&#25968;&#21015;&#34920;&#21518;&#65292;&#20363;&#22914; <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">int</span> printf<span class="br0">(</span><span class="kw4">const</span> <span class="kw4">char</span><span class="sy2">*</span> format, ...<span class="br0">)</span><span class="sy4">;</span></span></span> &#65292;&#21487;&#20197;&#21069;&#38468;&#21487;&#36873;&#30340;&#36887;&#21495;&#12290;&#35821;&#27861;&#19978;&#30340;&#39069;&#22806;&#32454;&#33410;&#12289;&#33258;&#21160;&#21442;&#25968;&#36716;&#25442;&#21450;&#26367;&#29992;&#39033;&#35265;<a href="cpp-language-variadic_arguments.html">&#21464;&#21442;&#25968;</a>&#12290;</p>
<p>&#20026;&#20174;&#20989;&#25968;&#20307;&#20869;&#35775;&#38382;&#21487;&#21464;&#21442;&#25968;&#65292;&#26631;&#20934;&#24211;&#25552;&#20379;&#19979;&#21015;&#24211;&#35774;&#26045;&#65306;</p>
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<div>&#23450;&#20041;&#20110;&#22836;&#25991;&#20214; <code><a href="cpp-header-cstdarg.html">&lt;cstdarg&gt;</a></code></div>
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<div><a href="cpp-utility-variadic-va_start.html"><span class="t-lines"><span>va_start</span></span></a></div>
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<td>&#21551;&#29992;&#23545;&#21487;&#21464;&#20989;&#25968;&#23454;&#21442;&#30340;&#35775;&#38382;<br />
<span class="t-mark">(&#23439;&#20989;&#25968;)</span></td>
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<div><a href="cpp-utility-variadic-va_arg.html"><span class="t-lines"><span>va_arg</span></span></a></div>
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<td>&#35775;&#38382;&#19979;&#19968;&#20010;&#21487;&#21464;&#20989;&#25968;&#23454;&#21442;<br />
<span class="t-mark">(&#23439;&#20989;&#25968;)</span></td>
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<div><a href="cpp-utility-variadic-va_copy.html"><span class="t-lines"><span>va_copy</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
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<td>&#21046;&#36896;&#21487;&#21464;&#20989;&#25968;&#23454;&#21442;&#30340;&#21103;&#26412;<br />
<span class="t-mark">(&#23439;&#20989;&#25968;)</span></td>
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<div><a href="cpp-utility-variadic-va_end.html"><span class="t-lines"><span>va_end</span></span></a></div>
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<td>&#32467;&#26463;&#23545;&#21487;&#21464;&#20989;&#25968;&#23454;&#21442;&#30340;&#36941;&#21382;<br />
<span class="t-mark">(&#23439;&#20989;&#25968;)</span></td>
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<div><a href="cpp-utility-variadic-va_list.html"><span class="t-lines"><span>va_list</span></span></a></div>
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<td>&#20445;&#26377; va_start&#12289;va_arg&#12289;va_end &#21644; va_copy &#25152;&#38656;&#30340;&#20449;&#24687;<br />
<span class="t-mark">(typedef)</span></td>
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<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">&#31034;&#20363;</span></h3>
<div class="t-example">
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<pre class="de1"><span class="co2">#include &lt;iostream&gt;</span>
<span class="co2">#include &lt;cstdarg&gt;</span>
<span class="kw4">void</span> simple_printf<span class="br0">(</span><span class="kw4">const</span> <span class="kw4">char</span><span class="sy2">*</span> fmt...<span class="br0">)</span> <span class="co1">// C &#39118;&#26684; &quot;const char* fmt, ...&quot; &#20134;&#21512;&#27861;</span>
<span class="br0">{</span>
<span class="kw4">va_list</span> args<span class="sy4">;</span>
<a href="cpp-utility-variadic-va_start.html"><span class="kw961">va_start</span></a><span class="br0">(</span>args, fmt<span class="br0">)</span><span class="sy4">;</span>
<span class="kw1">while</span> <span class="br0">(</span><span class="sy2">*</span>fmt <span class="sy3">!</span><span class="sy1">=</span> <span class="st0">&#39;<span class="es5">\0</span>&#39;</span><span class="br0">)</span> <span class="br0">{</span>
<span class="kw1">if</span> <span class="br0">(</span><span class="sy2">*</span>fmt <span class="sy1">==</span> <span class="st0">&#39;d&#39;</span><span class="br0">)</span> <span class="br0">{</span>
<span class="kw4">int</span> i <span class="sy1">=</span> <a href="cpp-utility-variadic-va_arg.html"><span class="kw963">va_arg</span></a><span class="br0">(</span>args, <span class="kw4">int</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> i <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<span class="br0">}</span> <span class="kw1">else</span> <span class="kw1">if</span> <span class="br0">(</span><span class="sy2">*</span>fmt <span class="sy1">==</span> <span class="st0">&#39;c&#39;</span><span class="br0">)</span> <span class="br0">{</span>
<span class="co1">// &#27880;&#24847;&#33258;&#21160;&#36716;&#25442;&#21040;&#25972;&#25968;&#31867;&#22411;</span>
<span class="kw4">int</span> c <span class="sy1">=</span> <a href="cpp-utility-variadic-va_arg.html"><span class="kw963">va_arg</span></a><span class="br0">(</span>args, <span class="kw4">int</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="kw1">static_cast</span><span class="sy1">&lt;</span><span class="kw4">char</span><span class="sy1">&gt;</span><span class="br0">(</span>c<span class="br0">)</span> <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<span class="br0">}</span> <span class="kw1">else</span> <span class="kw1">if</span> <span class="br0">(</span><span class="sy2">*</span>fmt <span class="sy1">==</span> <span class="st0">&#39;f&#39;</span><span class="br0">)</span> <span class="br0">{</span>
<span class="kw4">double</span> d <span class="sy1">=</span> <a href="cpp-utility-variadic-va_arg.html"><span class="kw963">va_arg</span></a><span class="br0">(</span>args, <span class="kw4">double</span><span class="br0">)</span><span class="sy4">;</span>
<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> d <span class="sy1">&lt;&lt;</span> <span class="st0">&#39;<span class="es1">\n</span>&#39;</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="sy2">++</span>fmt<span class="sy4">;</span>
<span class="br0">}</span>
<a href="cpp-utility-variadic-va_end.html"><span class="kw964">va_end</span></a><span class="br0">(</span>args<span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span>
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
simple_printf<span class="br0">(</span><span class="st0">&quot;dcff&quot;</span>, <span class="nu0">3</span>, <span class="st0">&#39;a&#39;</span>, <span class="nu16">1.999</span>, <span class="nu16">42.5</span><span class="br0">)</span><span class="sy4">;</span>
<span class="br0">}</span></pre></div>
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<p>&#36755;&#20986;&#65306;</p>
<div dir="ltr" class="mw-geshi" style="text-align: left;">
<div class="text source-text">
<pre class="de1">3
a
1.999
42.5</pre></div>
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<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">&#21442;&#38405;</span></h3>
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